Bedbugs are small, reddish-brown parasitic insects that bite the exposed skin of sleeping humans and animals to feed on their blood. Although bedbugs aren't known to spread disease, they can cause other public health and economic issues.

About the size of an apple seed, bedbugs hide in the cracks and crevices of beds, box springs, headboards, bed frames and any other objects around a bed. The risk of encountering bedbugs increases if you spend time in places with high turnovers of nighttime guests — such as hotels, hospitals or homeless shelters.

If you have bedbugs in your home, professional extermination is recommended.

It can be difficult to distinguish bedbug bites from other insect bites or rashes. In general, the sites of bedbug bites usually are:

Red, often with a darker red spot in the middle

Itchy

Arranged in a rough line or in a cluster

Located on the face, neck, arms and hands

Some people have no reaction to bedbug bites, while others experience an allergic reaction that can include severe itching, blisters or hives.

When to see a doctor

If you experience allergic reactions or severe skin reactions to bedbug bites, see your doctor for professional treatment.

Bedbug infestations may be linked to:

Increased international travel

Changes in pest control practices

Insecticide resistance

Where do they hide?

Bedbug infestations usually occur around or near where people sleep. They hide in the cracks and crevices of:

Mattresses

Box springs

Bed frames

Headboards

Objects or clutter near beds

They can also be found:

Under peeling paint and loose wallpaper

Under carpeting near baseboards

In upholstered furniture seams

Under light switch plates or electrical outlets

How do they spread?

Bedbugs are great hitchhikers. They can move from one site to another by traveling on clothing, luggage, furniture, bedding and boxes.

Bedbugs can crawl about as fast as a ladybug, and can easily travel between floors and rooms in hotels or apartment complexes.

Sign of uncleanliness?

Bedbugs don't care if their environment is clean or dirty. All they need is a warm host and plenty of hiding places.

Bedbugs are more common in crowded lodgings that experience high turnover in occupancy, such as:

Apartment complexes

Dorm rooms

Homeless shelters

Hotels

Cruise ships

Trains and buses

Refugee camps

Most bedbug bites require no medical treatment. Talk to your doctor if you experience an allergic reaction to the bites or if you develop a skin infection after scratching the bites.

What you can do

You may want to prepare a list that includes:

A detailed description of your symptoms

History of recent international travel

History of recent hotel stays

All the medications and supplements you take

What to expect from your doctor

Your doctor will carefully examine your bite sites and ask questions about the types of insects you might have been exposed to recently.

If you suspect that you're being bitten by bedbugs, immediately inspect your home for the insects. Thoroughly examine crevices in walls, mattresses and furniture. You may need to perform your inspection at night when bedbugs are active.

Look for these signs:

Dark specks. Typically found along mattress seams, these specks are bedbug excrement.

Empty exoskeletons. Bedbugs molt five times before becoming adults. These empty skins are pale yellow.

Rusty or reddish stains. You may find small smears of blood on your bed sheets where you accidentally crushed a bedbug.

The itchy red spots associated with bedbug bites usually disappear on their own within a week or two. You might speed your recovery by using:

A skin cream containing hydrocortisone (Cortaid)

An oral antihistamine, such as diphenhydramine (Benadryl)

If you develop a skin infection from scratching bedbug bites, your doctor may prescribe an antibiotic.

Treating your home

Once your symptoms are treated, you must tackle the underlying infestation. This can be difficult because bedbugs hide so well and can live several months without eating. Your best bet may be to hire a professional exterminator, who may use a combination of pesticides and nonchemical treatments.

Nonchemical treatments may include:

Vacuuming. A thorough vacuuming of cracks and crevices can physically remove bedbugs from an area. Empty the vacuum after each use.

Laundering. Washing and drying items in a dryer on a high setting will kill bedbugs in clothing or linens.

Freezing. Bedbugs are also vulnerable to temperatures below 32 F (0 C), but you'd need to leave the items outdoors or in the freezer for several days.

Some professional exterminators use portable devices to raise the temperature of a room to a lethal temperature. All stages of bedbugs can be killed at 122 F (50 C). In some cases, you may have to throw out heavily infested items such as mattresses or couches.

Preventing bites

Cover up. Because bedbugs don't tend to burrow under clothing, you may be able to avoid bites by wearing pajamas that cover as much skin as possible.

Bug spray. Insect repellents designed to protect against mosquitoes or ticks aren't very effective against bedbugs.

Mosquito netting. Bed nets impregnated with the pesticide permethrin may help protect sleepers against bedbug bites. However, this practice may be helping bedbugs develop resistance to this pesticide.

Preventing infestations

Secondhand items. Inspect used mattresses and upholstered furniture carefully before bringing them into your home.

Hotel precautions. Check mattress seams for bedbug excrement and place your luggage on tables or dressers instead of on the floor.

Birds and bats. Eliminate any neighboring bird and bat habitats that may serve as a refuge for bedbugs.

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